Millions of Americans suffer from sensorineural hearing impairment, a type of hearing loss for which use of a hearing aid is the primary mans of rehabilitation. This is particularly true among those over age 65, of whom 25-455 have significant hearing loss. This proposal describes a device use for state-of-the-art Complete Hearing Aid Selection an Evaluation (CHASE). In Phase I of this project, the software and hardware needed for CASE will be developed and a prototype will be constructed. The prototype will then be evaluated in a subsequent phase (Phase II) of this project.